STEP ONEHEAT oven to 350°F. Whisk flour, baking powder and salt in medium bowl until blended.
STEP TWOBEAT shortening and sugar in large bowl with mixer on high speed until light and fluffy, about 3 minutes.
STEP THREEBLEND in egg, milk and vanilla. Gradually blend in flour mixture.
STEP FOURDIVIDE dough in half. Roll out each half on lightly floured surface to 1/4-inch thickness for crisp cookies or 3/8-inch thickness for softer cookies. Cut with 2 to 3-inch cookie cutters. Place 2 inches apart on baking sheet.
STEP FIVESPRINKLE with decorator sugar, if desired. Bake 8 to 10 minutes or until bottom edges are very light brown. Cool 2 minutes on baking sheet. Remove to wire rack to cool completely. Frost, if desired.